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III IIIIIIIillllllll <br />989 <br />Mountain Coal Company <br />West Elk Mine <br />Post Office Bmc 591 <br />Sarnaset, Colorado 81134 <br />Tekplwrb 970 929.5015 <br />Fax 9709235595 <br />September 12, 1996 <br />Mr. Michael Boulay <br />Colorado Division of Minerals and Geology <br />1313 Sherman Street, Room 215 <br />Denver, CO 80203 <br />RE: Minor Revision No. 196; West Elk Mine; Permit No. C-80.007 <br />Deaz Mr. Boulay: <br />.µy~IC v i.cCW9Y <br />Mountain Coal Company (MCC) requests a minor revision to revise the West Elk Mine's B seam <br />mine plan. MCC proposes to mine two short panels in Section 21, as opposed to three as shown <br />in the current permit document, and also proposes to rotate the east longwall panels 10 degees to <br />the south. Please find enclosed revised Map 52, 'B-Seam Mme Plan" and a Subsidence <br />Evaluation of the revised panel layouts prepared by Wright Water Engineers. <br />MCC originally planned to mine three panels in Section 21 in the years 2021 to 2025. However, <br />MCC now plans to mine these panels in the years 1996 to 2000 as a result of mine development <br />shortfalls that occurred in 1995. It has been decided that these panels will be mined following <br />completion of the panels in Jumbo Mountain. The panel geometry is also revised to allow a larger <br />barrier pillar under Sylvester Gulch to reduce the risk of roof damage in the adjacent long term <br />main entries. This revision also reduces the number of panels in section 21 to two, rather than <br />three. This change is shghtly offset by increased panel width. <br />Panel reorientation for the longwall panels to the east will improve roof and rib conditions by <br />mining farther off pazallel to the coal cleat and the major roof joint orientation in the mine. This <br />change was proposed after observing Bound conditions in other areas of the mine, where several <br />roof falls occurred as block type failures when the major rock joint orientation occuaed at low <br />angles to entry headings. Rib sloughage has also been observed to increase due to mining at a <br />low angle to the coal cleat. The panel rotation 10 degees south will significantly reduce MCC's <br />miners' exposure to roof and rib hazards without reducing coal recovery, <br />Wright Water Engineers (WWE) has prepared for MCC a Subsidence Evaluation of the above <br />described revised panel layout. The evaluation concluded that the revised panel layout will not <br />change the effects of subsidence from those projected in Exhibit 60 contained in the currently <br />approved permit document. This evaluation should be added to Exhibit 60 of MCC's permit <br />document. <br />/\ <br />~r}" 16 1996 <br />